Patients are often treated systemically with anticoagulants that prevent their blood from clotting. Anticoagulants are typically used during medical procedures that require introducing a medical instrument into a patient's body through an artery. An example of such a procedure is a percutaneous transluminal coronary angioplasty (PTCA), which involves introducing a stent through the arteries. Such procedure leave a puncture wound in the artery where the medical instruments, such as a PTCA catheter, are introduced. The puncture extends through the skin, through the tissue under the skin, and into the artery.
Arterial punctures do not close readily, especially when a patient has been treated with an anticoagulant such as heparin. A conventional solution to sealing arterial punctures is to apply pressure to the wound site for many hours after the medical procedure. Another technique is to introduce a small deflated balloon into the artery, inflate it, and pull it up against the puncture so as to seal the artery off from the puncture. Then a coagulant or other clotting agent may be introduced into the puncture without entering the artery. See, for example, U.S. Pat. Nos. 5,108,421; 5,383,986; 5,626,601; and 6,017,359. Once the puncture has sufficiently sealed, the balloon is deflated and removed. Another method involves introducing a temporary or permanent barrier such as a plug, sponge, or gelation slurry. See, for example, U.S. Pat. Nos. 4,890,612; 4,852,568; 5,437,631; 5,782,860; 6,045,570; 6,071,301; and 6,315,753.
Another method includes injecting a wound site or pseudoaneurysm with a coagulant such as thrombin to accelerate clotting at the treatment site. Yet another solution to treating arterial punctures involves treatment of blood in a patient that has been given an anticoagulant such as heparin. In such a procedure, anticoagulated blood is removed from the patient. The blood is then treated to remove the heparin from the blood and then the blood is reintroduced into the patient, see, for example, U.S. Pat. No. 6,159,232 and PCT Application No. PCT/US00/15068, Such treatments conventionally require the use of complicated devices, bioactive coagulants, extra steps for removal of the anticoagulant, or a long delay before the patient can be released.
What is needed is a simple system that reproducibly, safely, and inexpensively provides a quick and effective seal to the wound site of a patient treated with anticoagulants. The use of products derived from blood not taken from the patient or recombinantly produced molecules should preferably be avoided for reasons of safety, cost, and simplicity.